CN111132945B

CN111132945B - Coatings with controlled roughness and microstructure

Info

Publication number: CN111132945B
Application number: CN201880062318.9A
Authority: CN
Inventors: H·B·德克尔; S·D·哈特; K·W·科齐三世; C·A·保尔森
Original assignee: Corning Inc
Current assignee: Corning Inc
Priority date: 2017-07-31
Filing date: 2018-07-30
Publication date: 2022-10-21
Anticipated expiration: 2038-07-30
Also published as: CN111132945A; WO2019027909A1; US20210130230A1; US11072559B2; TW201910289A; TWI758520B

Abstract

The article includes a glass, glass-ceramic, or ceramic substrate comprising a major surface. The functional coating is disposed over a major surface of the substrate. The coating includes a first portion disposed over the major surface. One or more discontinuous layers are disposed on the first portion. A second portion is disposed over the one or more discontinuous layers. The one or more discontinuous layers comprise a microstructure different from one of the first and second portions, and the coating has an average optical transmission greater than about 10% over a visible wavelength range of about 450nm to about 650 nm.

Description

Coatings with controlled roughness and microstructure

CROSS-REFERENCE TO RELATED APPLICATIONS

Priority of U.S. provisional application serial No. 62/539,112, filed 2017, month 7, 31, in accordance with 35u.s.c. § 119, herein incorporated by reference in its entirety.

Technical Field

The present disclosure relates to articles having functional coatings, and more particularly, to articles having hard functional coatings with controlled roughness and microstructure (particularly, optical properties).

Background

Transparent hard coatings (e.g., alN) _x 、AlO _x N _y 、Al ₂ O ₃ 、ZrO ₂ -Al ₂ O ₃ 、SiN _x 、SiO _x N _y Diamond or diamond-like carbon coating and/or ZrO ₂ Possibly having an amorphous/polycrystalline or semi-crystalline microstructure) depending on their manufacturing conditions. These coatings may be valuable for a variety of applications. For example, such coatings may be used as hard and scratch or abrasion resistant coatings on substrates, with high optical clarity. These materials may have a natural tendency to form polycrystalline or semi-crystalline microstructures. Such polycrystalline microstructures may impart certain benefits such as mechanical toughness or piezoelectric properties. To maximize the benefits of these properties, it may be advantageous to engineer the crystallite size (e.g., reduce crystallite size to control coating surface roughness). The surface roughness of the hard coating is believed to play an important role in certain mechanical wear performance tests, frictional contact events, and durability of thin organic low friction layers deposited on top of the hard coating, such as easy-to-clean coatings, e.g., 1-10 nanometer (nm) thick fluorochemical silane coatings.

Accordingly, there is a need for methods of controlling polycrystalline or semi-crystalline hard coating microstructure, crystallite size and surface roughness while maintaining optical transparency of the underlying substrate for use in displays, touch screens, eyewear, windows and similar applications. Thus, there is also a need for articles having a hard functional coating with controlled roughness and microstructure (particularly optical properties).

Disclosure of Invention

According to some aspects of the present disclosure, an article includes a glass, glass-ceramic, or ceramic substrate comprising a major surface. The functional coating is disposed over a major surface of the substrate. The coating includes a first portion disposed over the major surface. One or more discontinuous layers are disposed on the first portion. A second portion is disposed over the one or more discontinuous layers. The one or more discontinuous layers comprise a microstructure different from one of the first and second portions and the coating has an average optical transmission greater than about 10% over a visible wavelength range of about 450nm to about 650 nm.

According to some aspects of the present disclosure, an article includes a substrate comprising a major surface and a glass, glass-ceramic, or ceramic composition. The functional coating is disposed over a major surface of the substrate to form a coated surface. The coating includes a first portion disposed over the major surface. A plurality of discontinuities are disposed over the first portion and comprise a different microstructure than the first portion. A second portion is disposed over the plurality of discontinuous layers. The discontinuous layers comprise an optical transmission of greater than about 85% over a visible wavelength range of about 450nm to about 650nm, and each of the discontinuous layers has a thickness of 100nm or less.

In accordance with other aspects of the present disclosure, a consumer electronic product includes a housing having a front surface, a back surface, and side surfaces. An electronic assembly is at least partially located within the housing, the electronic assembly including at least a controller, a memory, and a display, the display being located at or adjacent to the front surface of the housing. The cover glass is disposed over the display. At least one of a portion of the housing or the cover glass comprises the article described above.

Additional features and advantages of the disclosure are set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the various embodiments described herein, including the detailed description which follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and are intended to provide an overview or framework for understanding the nature and character of the disclosure and the appended claims.

The accompanying drawings are included to provide a further understanding of the principles of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiments of the disclosure and, together with the description, serve to explain, for example, the principles and operations of the disclosure. It is to be understood that the various features of the present disclosure disclosed in the specification and the drawings may be used in any and all combinations. As a non-limiting example, various features of the present disclosure may be combined with each other according to the following embodiments.

According to a first aspect, there is provided an article comprising: a glass, glass ceramic, or ceramic substrate comprising a major surface, and a functional coating disposed over the major surface of the substrate. The coating comprises: the system includes a first portion disposed over a major surface, one or more discontinuous layers disposed over the first portion, and a second portion disposed over the one or more discontinuous layers. The one or more discontinuous layers comprise a microstructure different from one of the first and second portions, and the coating has an average optical transmission greater than about 10% over a visible wavelength range of about 450nm to about 650 nm.

According to a second aspect, there is provided the article of aspect 1, wherein the one or more discontinuous layers comprise a microstructure that is different from both the first and second portions.

According to a third aspect, there is provided the article of any one of

aspects

1 and 2, wherein the one or more discontinuous layers have an amorphous microstructure.

According to a fourth aspect of any one of aspects 1 to 3, there is provided the article of any one of aspects 1 to 3, wherein the first and second portions of the coating each comprise a plurality of layers, and the coating has an average optical transmission of greater than about 50%.

According to aspect 5, there is provided the article of any one of aspects 1-4, wherein the second portion of the coating within about 100nm of the discontinuous layer comprises an average microstructured crystal size that is less than the average microstructured crystal size of the first portion within about 100nm of the discontinuous layer.

According to a 6 th aspect, there is provided the article of any one of aspects 1-5, wherein each of the one or more discontinuous layers comprises a thickness of about 50nm or less.

According to a 7 th aspect, there is provided the article of aspect 6, wherein the one or more discontinuous layers comprise a thickness of about 10nm or less.

According to an 8 th aspect, there is provided the article of any one of aspects 1-7, wherein the one or more discontinuous layers are porous.

According to a 9 th aspect, there is provided the article of any one of aspects 1-8, wherein at least one of the first and second portions comprises a thickness of about 0.1 μm to about 2 μm.

According to a10 th aspect, there is provided the article of any one of aspects 1-8, wherein the one or more discontinuous layers comprises three layers, and the article further comprises a plurality of spacing layers (spacing layers) located between the one or more discontinuous layers (spacing layers).

According to an 11 th aspect, there is provided the article of any one of aspects 1-10, and they further comprise an easy-to-clean (ETC) coating disposed over the second portion of the functional coating.

According to a 12 th aspect, there is provided the article of any one of aspects 1-11, wherein the coating comprises a surface roughness of about 5nm Rq or less.

According to a 13 th aspect, there is provided an article comprising: a substrate comprising a major surface and a glass, glass-ceramic, or ceramic composition, and a functional coating disposed over the major surface of the substrate to form a coated surface. The coating comprises: a first portion disposed over a major surface, a plurality of discontinuous layers disposed over the first portion and comprising a different microstructure than the first portion, and a second portion disposed over the plurality of discontinuous layers. The discontinuous layers comprise an optical transmission of greater than about 85% over a visible wavelength range of about 450nm to about 650nm, and each of the discontinuous layers has a thickness of 100nm or less.

According to a 14 th aspect, there is provided the article of aspect 13, wherein the plurality of discontinuous layers comprise a refractive index difference of about 0.1 or greater relative to any of the first and second portions, and wherein each of the discontinuous layers has a thickness of about 5nm or greater.

According to a 15 th aspect, there is provided the article of any one of aspects 13 and 14, wherein the coating comprises a surface roughness of about 5nm Rq or less.

According to a 16 th aspect, there is provided the article of any one of aspects 13-15, wherein the first and second portions comprise first and second bulk layers, respectively, and the first and second bulk layers comprise a thickness of about 200nm or greater, respectively.

According to a 17 th aspect there is provided the article of aspect 16, wherein the first and second bulk layers are each in contact with at least one of the plurality of discontinuous layers.

According to an 18 th aspect, there is provided the article of any one of aspects 13-17, wherein the plurality of discontinuous layers comprises Al ₂ O ₃ 。

According to a 19 th aspect, there is provided the article of any one of aspects 13-18, wherein the substrate comprises a compressively stressed region extending from the major surface to a first selected depth into the substrate.

According to a 20 th aspect, there is provided the article of any one of aspects 13-19, wherein the plurality of discontinuous layers comprise a thickness that is about 10% or less of the total thickness of the functional coating.

According to a 21 st aspect, there is provided a consumer electronics product comprising: a housing having a front surface, a back surface, and side surfaces; an electronic assembly at least partially within the housing, the electronic assembly including at least a controller, a memory, and a display, the display being located at or adjacent to the front surface of the housing; and a cover glass disposed over the display. At least one of the housing or a portion of the cover glass comprises the article of any of aspects 1-20.

According to a 22 th aspect, there is provided the article of any one of aspects 13-19, wherein the coated surface has a hardness of about 12 or greater as measured by a berkovich nanoindentation at an indentation depth of about 100nm or greater.

According to a 23 th aspect, there is provided the article of any one of aspects 13-19, wherein the first portion and/or the second portion of the functional coating comprises a polycrystalline or semi-crystalline material.

According to a 24 th aspect, there is provided the article of any one of aspects 13-19, wherein the first portion and/or the second portion of the functional coating comprises a polycrystalline or semi-crystalline material comprising AlOxNy, wherein x (representing the mole fraction of oxygen relative to aluminum) is from about 0.02 to about 0.25; and wherein y (representing the mole fraction of nitrogen relative to aluminum) is from about 0.75 to about 0.98.

According to a 25 th aspect, there is provided a method of forming a functional coating on a substrate, comprising the steps of: depositing a first portion on a major surface of a substrate; depositing one or more discontinuous layers on the first portion, the one or more discontinuous layers comprising a microstructure different from the first portion and having an optical transmission in the visible wavelength range of about 450nm to about 650nm of greater than about 85%; and depositing a second portion on the one or more discontinuous layers.

According to a 26 th aspect there is provided the method of aspect 25, wherein the step of depositing one or more discontinuous layers further comprises the step of depositing the one or more discontinuous layers to comprise a thickness of about 100nm or less.

Drawings

The following is a brief description of the drawings taken in conjunction with the accompanying drawings. The figures are not necessarily to scale, and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.

In the drawings:

FIG. 1A is a cross-sectional view of an article including a film according to at least one example;

FIG. 1B is a cross-sectional view of an article including a film according to at least one example;

FIG. 2 is a consumer electronic product according to at least one example;

FIG. 3 is a model first surface reflectance plot for 5 incident angles for various embodiments of the present disclosure as well as comparative examples;

FIG. 4 is a model dual surface transmission plot for 5 ° incident angles for various examples of the present disclosure as well as comparative examples;

fig. 5A is a first surface reflectance D65 color plot for all observation angles from 0 ° to 90 ° for various embodiments and comparative examples of the present disclosure;

FIG. 5B is a graph of dual surface transmission D65 color for all observation angles from 0 to 90 for various embodiments of the present disclosure and comparative examples;

FIG. 6 is a first surface reflectance plot for a 6 incident angle for at least one embodiment of the present disclosure and a comparative example;

FIG. 7 is a dual surface transmission plot for 6 incident angles for at least one embodiment of the present disclosure and comparative examples;

FIG. 8 is a first surface reflectance plot at a 5 incident angle in accordance with at least one embodiment of the present disclosure;

FIG. 9 is a graph of dual surface transmission at a 5 incident angle in accordance with at least one embodiment of the present disclosure;

fig. 10A is a first surface reflection D65 color plot for all observation angles of 0 ° to 90 ° for various embodiments of the present disclosure and comparative examples; and

fig. 10B is a dual surface transmission D65 color plot for all observation angles from 0 ° to 90 ° for various examples of the present disclosure as well as comparative examples.

FIG. 11 is a graph of hardness versus indentation depth for films of various thicknesses on a substrate.

Detailed Description

Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described in the following description and claims, as well as the appended drawings.

As used herein, the term "and/or," when used in reference to two or more items, means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a composition is described as containing components a, B and/or C, the composition may contain only a; only contains B; only contains C; a combination comprising A and B; a combination comprising A and C; a combination comprising B and C; or a combination comprising A, B and C.

In this document, relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.

Modifications of the disclosure will occur to those skilled in the art and to those who make and use the disclosure. Therefore, it is to be understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and are not intended to limit the scope of the disclosure, which is defined by the following claims, which are to be read in accordance with the principles of patent law, to include the doctrine of equivalents.

For the purposes of this disclosure, the term "coupled" (in all its forms: connected, and the like) generally means that two components are joined to one another either directly or indirectly (electrically or mechanically). Such engagement may naturally be static or may naturally be movable. Such joining may be achieved through the two components and any additional intermediate elements (electrically or mechanically) that are integrally formed as a single unitary piece with each other or with the two components. Such engagement may naturally be permanent, or may naturally be removable or disengageable, unless otherwise indicated.

As used herein, the term "about" means that amounts, sizes, formulations, parameters, and other variables and characteristics are not and need not be exact, but may be approximate and/or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off and measurement error and the like, and other factors known to those of skill in the art.

When the term "about" is used to describe a value or an endpoint of a range, it is to be understood that the disclosure includes the particular value or endpoint referenced. Whether or not the numerical values or range endpoints of the specification recite "about," the numerical values or range endpoints are intended to include two embodiments: one modified with "about" and one not. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

As used herein, the terms "substantially", "essentially" and variations thereof are intended to indicate that the feature so described is equal or approximately the same as the value or description. For example, a "substantially flat" surface is intended to mean a flat or near flat surface. Further, "substantially" is intended to mean that the two values are equal or approximately equal. In some embodiments, "substantially" may mean values within about 10% of each other, such as within about 5% of each other, or within about 2% of each other.

Directional terminology used herein, such as upper, lower, left, right, front, rear, top, bottom, is for reference only to the accompanying drawings and is not intended to be absolute.

As used herein, the terms "the," "an," or "an" mean "at least one," and should not be limited to "only one," unless expressly stated to the contrary. Thus, for example, reference to "a component" includes embodiments having two or more such components, unless the context clearly indicates otherwise.

Referring now to fig. 1A and 1B, a laminated article 10 includes a film 14 and a substrate 18. As explained in detail below, the film 14 may be a multilayer structure that provides a variety of functional properties (e.g., scratch resistance) and optical properties (e.g., anti-reflection and color neutrality).

Substrate 18 may have opposing

major surfaces

18A, 18B. Substrate 18 may also define one or more minor surfaces. For purposes of this disclosure, the term "major surface" may be one or more of the opposing

major surfaces

18A, 18B and/or minor surfaces. According to various examples, the film 14 may be disposed on a major surface of the substrate 18. Substrate 18 may be a substantially flat sheet, but other examples may employ a curved or any other shape or configuration of substrate 18. Additionally or alternatively, the thickness of substrate 18 may vary along one or more dimensions thereof for aesthetic and/or functional reasons. For example, the edges of the substrate 18 may be thicker than a more central region of the glass-based substrate 18, or vice versa. The length, width, and thickness dimensions of substrate 18 may also vary depending on the application or use of article 10.

As explained above, the article 10 includes a substrate 18 on which the film 14 is placed or disposed. Substrate 18 may comprise glass, glass-ceramic, ceramic materials, and/or combinations thereof. For the purposes of this disclosure, the term "glass-based" may refer to glass, glass-ceramic, and/or ceramic materials. The term "glass-based" as used herein is intended to include any material made at least in part from glass, including glass, glass-ceramics, and sapphire. "glass-ceramic" includes materials produced by the controlled crystallization of glass. In an embodiment, the glass-ceramic has a crystallinity of from about 1% to about 99%. Examples of suitable glass-ceramics may include Li ₂ O-Al ₂ O ₃ -SiO ₂ System (i.e., LAS system) glass-ceramic, mgO-Al ₂ O ₃ -SiO ₂ System (i.e., MAS system) glass-ceramic, znO × Al ₂ O ₃ ×nSiO ₂ (i.e., ZAS systems) and/or glass-ceramics comprising a predominant crystalline phase with β -quartz solid solution, β -spodumene, cordierite, and lithium disilicate. The glass-ceramic substrate may be strengthened using the chemical strengthening processes disclosed herein. In one or more embodiments, the MAS system glass-ceramic substrate may be in Li ₂ SO ₄ Strengthening in molten salt, so that 2Li can be generated ⁺ Is coated with Mg ²⁺ And (4) exchanging. According to various examples, substrate 18 may be a glass-based substrate. In the glass-based example of substrate 18, substrate 18 may be strengthened or strong, as explained in more detail below. The substrate 18 may be substantially clear, transparent, and/or free of light scattering. In the glass-based example of substrate 18, substrate 18 may have a refractive index of about 1.45 to about 1.55. Further, substrate 18 of article 10 may include sapphire and/or a polymeric material. Examples of suitable polymers include, but are not limited to: thermoplastic materials including Polystyrene (PS) (including styrene copolymers and blends), polycarbonate (PC) (including copolymers and blends), polyesters (including copolymers and blends, including polyethylene glycol terephthalate and polyethylene glycol terephthalate copolymers), polyolefins (PO) and cyclic polyolefins (cyclic PO), polyvinyl chloride(PVC), acrylic polymers including Polymethylmethacrylate (PMMA) (including copolymers and blends), thermoplastic urethanes (TPU), polyetherimides (PEI), and blends of these polymers with each other. Other exemplary polymers include epoxy resins, styrenic resins, phenolic resins, melamine resins, and silicone resins.

According to various examples, substrate 18 may have a thickness ranging from about 50 micrometers (microns or μm) to about 5 millimeters (mm). An exemplary thickness range for substrate 18 is 1 μm to 1000 μm or 100 μm to 500 μm. For example, substrate 18 may have a thickness as follows: about 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm or 1000 μm. According to other examples, glass-based substrate 18 may have a thickness of greater than or equal to about 1mm, about 2mm, about 3mm, about 4mm, or about 5 mm. In one or more specific examples, glass-based substrate 18 may have a thickness of 2mm or less than 1 mm. Substrate 18 may be acid polished or otherwise treated to remove or reduce the effects of surface imperfections.

Substrate 18 may be relatively pristine and flawless (e.g., having a low number of surface flaws or an average surface flaw size of less than about 1 μm). When strengthened or strengthened glass-based substrates 18 are employed, such substrates 18 may be characterized as having a high average flexural strength (when compared to an unreinforced or weak glass-based substrate 18) or a high surface strain to failure (when compared to an unreinforced or weak glass-based substrate 18) on one or more opposing major surfaces of such substrates 18.

Suitable substrates 18 may exhibit an elastic modulus (e.g., young's modulus) of about 30GPa to about 120 GPa. In some cases, the elastic modulus of the substrate may be about 30GPa to about 110GPa, about 30GPa to about 100GPa, about 30GPa to about 90GPa, about 30GPa to about 80GPa, about 30GPa to about 70GPa, about 40GPa to about 120GPa, about 50GPa to about 120GPa, about 60GPa to about 120GPa, about 70GPa to about 120GPa, and all ranges and subranges therebetween. The Young's modulus value or elastic modulus value of a substrate set forth in this disclosure refers to a measurement by a Resonant ultrasonic Spectroscopy technique of the general type set forth in ASTM E2001-13, entitled "Standard Guide for reactive ultra Spectroscopy for Defect Detection in Box Metallic and Non-Metallic Parts".

Various different processes may be employed to provide examples of glass-based substrate 18. For example, methods of forming glass-based substrate 18 include float glass processes and down-draw processes, such as fusion draw and slot draw.

Once formed, examples of glass-based substrate 18 may be strengthened to form strengthened glass-based substrate 18. As used herein, the term "strengthened glass-based substrate" will refer to a strengthened glass-based substrate 18 that adds residual compressive stress to the substrate 18 by post-fabrication processes by, for example, ion-exchanging smaller ions in the surface of the glass-based substrate 18 with larger alkali metal ions. However, other strengthening methods known in the art may be employed, such as the example of a thermal temper that may be employed to form strengthened glass-based substrate 18. As will be described below, the strengthened glass-based substrate includes a glass-based substrate 18, the glass-based substrate 18 having a surface compressive stress in a surface thereof (e.g., at least one of the opposing

major surfaces

18A, 18B and/or minor surfaces), and/or a body thereof that contributes to strength retention of the glass-based substrate 18.

Also as used herein, a "strong" glass-based substrate 18 is within the scope of the present disclosure. Robust substrates include glass-based substrates 18 that may or may not be subjected to a particular strengthening process to impart residual compressive stress, but still undergo manufacturing or post-manufacturing processing, steps or processes, which results in increased average strength/weibull modulus and/or strain to failure compared to a control substrate without a "robust" processing, step or process. For example, a strong glass-based substrate 18 may be formed with and/or polished to have an pristine surface that reduces the average flaw size and/or the number of flaws. Such strong glass-based substrates 18 may be defined as glass sheet articles or glass-based substrates having an average strain-to-failure greater than about 0.5%, 0.7%, 1%, 1.5%, or even greater than 2%. Such strong glass-based substrates 18 may be manufactured, for example, by protecting the pristine glass surfaces after the glass-based substrate 18 is melted and shaped. One example of such protection occurs in fusion draw processes, where the surface of the glass film does not come into contact with any part of the equipment or other surfaces after forming. Glass-based substrates 18 formed by fusion draw processes derive their strength from their original surface quality. The pristine surface quality may also be achieved by etching or polishing and subsequent protection of the glass-based substrate surface, as well as other methods known in the art.

In one or more embodiments, both the strengthened glass-based substrate 18 and the strong glass-based substrate 18 can have an average strain-to-failure of greater than about 0.5%, 0.7%, 1%, 1.5%, or even greater than 2% when tested using the ring-on-ring or ball-on-ring deflection test.

As described above, the glass-based examples of substrates 18 used in the laminated articles 10 described herein (see fig. 1A and 1B) may be chemically strengthened by an ion exchange process to provide strengthened glass-based substrates 18. The glass-based substrate 18 may also be strengthened by other methods known in the art, such as thermal tempering. In the ion exchange process, ions at or near the surface of the glass-based substrate 18 are exchanged with the larger metal ions of the salt bath, typically by immersing the glass-based substrate 18 in the molten salt bath for a predetermined period of time. According to various examples, the temperature of the molten salt bath is about 350 ℃ to 450 ℃, and the predetermined period of time is about 2 to about 8 hours. The incorporation of the larger ions into the glass-based substrate 18 strengthens the glass-based substrate 18 by creating a compressive stress in a near-surface region or regions at or near the surface (e.g., opposing

major surfaces

18A, 18B) of the glass-based substrate 18. A corresponding tensile stress is induced in a central region or a region at a distance from the surface of the glass-based substrate 18 to balance the compressive stress. Glass-based substrates 18 employing such strengthening processes may be more particularly described as chemically strengthened glass-based substrates 18 or ion-exchanged glass-based substrates 18. Herein, a glass-based substrate 18 that has not been strengthened is referred to as an "unreinforced" glass-based substrate 18; however, such "untempered" glass-based substrates may or may not be "strong" substrates as defined previously in this disclosure.

According to various examples, sodium ions in the chemically strengthened glass-based substrate 18 are replaced by potassium ions in a molten salt bath (e.g., a potassium nitrate bath), but other alkali metal ions having larger atomic radii (e.g., rubidium or cesium) may also replace smaller alkali metal ions in the glass. In some examples, the smaller alkali metal ions in the glass may be replaced by Ag ⁺ And (4) ion replacement. Similarly, other alkali metal salts, such as but not limited to sulfate, phosphate, and halide, etc., may be used in the ion exchange process.

Replacing smaller ions with larger ions at temperatures below where the glass network of the glass-based substrate 18 would relax creates an ion distribution on the surface of the strengthened glass-based substrate 18, which results in a stress profile. The larger volume of the incoming ions creates a Compressive Stress (CS) on the surface and a tension (center tension, or CT) in the center of the strengthened glass-based substrate 18. The depth of ion exchange can be described as the depth in the strengthened glass-based substrate 18 (i.e., the distance from the surface of the glass-based substrate to the central region of the glass-based substrate) at which ion exchange facilitated by the ion exchange process occurs. Thus, glass-based substrate 18 may have a compressive stress region.

Examples of strengthening of the glass-based substrate 18 may have a surface compressive stress greater than or equal to 300MPa, 400MPa, 450MPa, 500MPa, 550MPa, 600MPa, 650MPa, 700MPa, 750MPa, or greater than or equal to about 800 MPa. Strengthened glass-based substrate 18 can have a depth of compression (i.e., a first selected depth at which the compressive stress region extends from major surface 18A into the substrate) of about 15 μm to about 100 μm. In other examples, the glass-based substrate 18 may have a depth of compression of about 5 μm or more, 10 μm or more, 15 μm or more, 20 μm or more, 25 μm or more, 30 μm or more, 35 μm or more, 40 μm or more, 45 μm or more, or 50 μm or more in the glass-based substrate 18. According to various examples, the glass-based substrate 18 may have a depth of compression of about 15 μm or greater in the glass-based substrate 18. A central tension of about 10MPa or greater, 20MPa or greater, 30MPa or greater, 40MPa or greater, 42MPa or greater, 45MPa or greater, or about 50MPa or greater may be present in the glass-based substrate 18. The central tension can be less than or equal to about 100MPa, 95MPa, 90MPa, 85MPa, 80MPa, 75MPa, 70MPa, 65MPa, 60MPa, or less than or equal to about 55MPa. In one or more specific examples, strengthened glass-based substrate 18 has one or more of the following: a surface compressive stress greater than 500MPa, a depth of compression greater than 15 μm, and a central tension greater than 18MPa.

The compressive stress (including the surface CS) was measured by a surface stress meter (FSM) using a commercial instrument such as FSM-6000 manufactured by Orihara Industrial co. Surface stress measurement relies on the accurate measurement of the Stress Optical Coefficient (SOC), which is related to the birefringence of the glass. The SOC was then measured according to protocol C (Method of Glass dishes) as described in ASTM Standard C770-16, entitled "Standard Test Method for measuring Glass Stress-Optical Coefficient", which is incorporated herein by reference in its entirety. As used herein, DOC refers to the depth of change from compression to tension of the stress in a chemically strengthened aluminosilicate glass article described herein. Depending on the ion exchange process, DOC can be measured by FSM or scattered light polarizer (SCALP). When stress is generated in the glass article by exchanging potassium ions into the glass article, the DOC is measured using FSM. When stresses are generated in the glass article by exchanging sodium ions into the glass article, the DOC is measured using the SCALP. When stress is created in the glass article by exchanging both potassium and sodium ions into the glass, the DOC is measured by SCALP, as it is believed that the depth of exchange of sodium represents the DOC, and the depth of exchange of potassium ions represents the change in magnitude of the compressive stress (rather than the change in stress from compressive to tensile); in such glass articles, the exchange depth of potassium ions is measured by FSM. The maximum CT value is measured using the scattered light polarizer (scapp) technique known in the art.

Without being bound by theory, it is believed that strengthened glass-based substrates 18 having a surface compressive stress greater than 500MPa and a compressive depth greater than about 15 μm typically have a greater strain to failure than non-strengthened glass-based substrates 18 (or, in other words, glass-based substrates that have not been ion exchanged or any other strengthening). According to various examples, the benefits of one or more of the examples described herein may not be significant for non-strengthened or weakly strengthened types of glass-based substrates 18 that do not meet these surface compressive stress or depth of compression levels because of handling or common glass surface damage events in many typical applications. In other specific applications where the surface of the glass-based substrate 18 may be sufficiently protected from scratches or surface damage (by, for example, a protective coating or other layer), methods such as fusion forming may also be employed to produce a strong glass-based substrate 18 with a higher strain-to-failure by developing and protecting the pristine glass surface quality. In these alternative applications, the benefits of one or more of the examples described herein may be similarly realized.

Exemplary ion-exchangeable glasses that may be used for strengthened glass-based substrate 18 may include: an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition, although other glass compositions are also contemplated. As used herein, "ion-exchangeable" means that the glass-based substrate 18 is capable of exchanging cations located at or near the surface of the glass-based substrate with cations in the same valence state that are larger or smaller in size. An exemplary glass composition comprises SiO ₂ 、B ₂ O ₃ And Na ₂ O, wherein (SiO) ₂ +B ₂ O ₃ ) Not less than 66 mol% and Na ₂ O is more than or equal to 9 mol percent. In another example, the glass-based substrate 18 includes a glass composition having at least 6 wt.% alumina. In thatIn another example, the glass-based substrate 18 includes a glass composition having one or more alkaline earth oxides such that the alkaline earth oxide content is at least 5 wt.%. In some examples, suitable glass compositions further comprise K ₂ At least one of O, mgO, and CaO. In particular examples, the glass composition for glass-based substrate 18 may comprise: 61-75 mol% SiO ₂ (ii) a 7-15 mol% of Al ₂ O ₃ (ii) a 0-12 mol% of B ₂ O ₃ (ii) a 9-21 mol% of Na ₂ O;0-4 mol% of K ₂ O;0-7 mol% MgO; and 0-3 mol% CaO.

Another exemplary glass composition suitable for glass-based substrate 18 that may optionally be strengthened or strengthened comprises: 60-70 mol% SiO ₂ (ii) a 6-14 mol% Al ₂ O ₃ (ii) a 0-15 mol% of B ₂ O ₃ (ii) a 0-15 mol% Li ₂ O;0-20 mol% of Na ₂ O;0-10 mol% of K ₂ O;0-8 mol% MgO;0-10 mol% CaO;0-5 mol% of ZrO ₂ (ii) a 0-1 mol% of SnO ₂ (ii) a 0 to 1 mol% of CeO ₂ (ii) a Less than 50ppm As ₂ O ₃ (ii) a And less than 50ppm Sb ₂ O ₃ (ii) a Wherein 12 mol% is less than or equal to (Li) ₂ O+Na ₂ O+K ₂ O) is less than or equal to 20 mol percent, and 0 mol percent is less than or equal to (MgO + CaO) is less than or equal to 10 mol percent.

Another exemplary glass composition suitable for glass-based substrate 18 that may optionally be strengthened or strengthened comprises: 63.5-66.5 mol% SiO ₂ (ii) a 8-12 mol% of Al ₂ O ₃ (ii) a 0-3 mol% of B ₂ O ₃ (ii) a 0-5 mol% of Li ₂ O;8-18 mol% Na ₂ O;0-5 mol% of K ₂ O;1-7 mol% MgO;0-2.5 mol% CaO;0-3 mol% of ZrO ₂ (ii) a 0.05-0.25 mol% SnO ₂ (ii) a 0.05-0.5 mol% of CeO ₂ (ii) a Less than 50ppm of As ₂ O ₃ (ii) a And Sb of less than 50ppm ₂ O ₃ (ii) a Wherein 14 mol% is less than or equal to (Li) ₂ O+Na ₂ O+K ₂ O) is less than or equal to 18 mol percent,and 2 mol% is less than or equal to (MgO + CaO) and less than or equal to 7 mol%.

In one particular example, an alkali aluminosilicate glass composition suitable for glass-based substrate 18 that may optionally be strengthened or strengthened comprises: alumina, at least one alkali metal, and in some embodiments greater than 50 mole% SiO ₂ In other examples at least 58 mol% SiO ₂ And in other instances at least 60 mole% SiO ₂ Wherein the ratio (Al) ₂ O ₃ +B ₂ O ₃ ) Sigma modifier>1 wherein the proportions of the components are in mole% and the modifier is an alkali metal oxide. In a particular example, such a glass composition comprises: 58-72 mol% SiO ₂ 9-17 mol% of Al ₂ O ₃ 2-12 mol% of B ₂ O ₃ 8-16 mol% of Na ₂ O and 0-4 mol% of K ₂ O, wherein, the ratio (Al) ₂ O ₃ +B ₂ O ₃ ) Sigma modifier>1。

In another example, glass-based substrate 18, which may optionally be strengthened or strengthened, may include an alkali aluminosilicate glass composition comprising: 64-68 mol% SiO ₂ (ii) a 12-16 mol% Na ₂ O;8-12 mol% Al ₂ O ₃ (ii) a 0-3 mol% of B ₂ O ₃ (ii) a 2-5 mol% of K ₂ O;4-6 mol% MgO; and 0-5 mol% of CaO, wherein SiO is more than or equal to 66 mol% ₂ +B ₂ O ₃ CaO is less than or equal to 69 mol%; na (Na) ₂ O+K ₂ O+B ₂ O ₃ +MgO+CaO+SrO>10 mol%; mgO, caO and SrO are more than or equal to 5 mol% and less than or equal to 8 mol%; (Na) ₂ O+B ₂ O ₃ )≤Al ₂ O ₃ Less than or equal to 2 mol percent; na with the molar percent of more than or equal to 2 percent ₂ O≤Al ₂ O ₃ Less than or equal to 6 mol percent; and 4 mol% is less than or equal to (Na) ₂ O+K ₂ O)≤Al ₂ O ₃ Less than or equal to 10 mol percent.

According to various examples, examples of glass-based substrates 18 that may optionally be strengthened or strengthened may include alkali silicate glass compositions comprising:2 mol% or more of Al ₂ O ₃ And/or ZrO ₂ Or 4 mol% or more of Al ₂ O ₃ And/or ZrO ₂ 。

According to various examples, glass-based examples of substrate 18 may be formulated with 0-2 mole% of at least one fining agent selected from the group consisting of: na (Na) ₂ SO ₄ 、NaCl、NaF、NaBr、K ₂ SO ₄ KCl, KF, KBr and SnO ₂ 。

Still referring to fig. 1A and 1B, the film 14 (also referred to herein as a coating) is shown directly on the glass-based substrate 18, but it will be understood that one or more layers or films may be disposed between the film 14 and the substrate 18. The membrane 14 may be disposed on more than one surface of the substrate 18. Additionally, the film 14 may be disposed on the opposing

major surfaces

18A, 18B and minor surfaces of the substrate 18.

The term "film" when used with respect to film 14 and/or other films incorporated into the laminated article 10 includes one or more layers formed by any method known in the art, including discontinuous deposition or continuous deposition processes. Such layers may be in direct contact with each other. The layers may be formed of the same material or of more than one different material. In one or more alternative examples, such layers may have intervening layers of different materials disposed therebetween. In one or more examples, the film 14 may include one or more contiguous and uninterrupted layers and/or one or more discontinuous and interrupted layers (i.e., layers formed adjacent to each other having different materials). According to various examples, the film 14 is free of macro scratches or defects that are readily visible to the naked eye.

As used herein, the term "disposing" includes coating, depositing, and/or forming a material on a surface using any method known in the art. The arranged material may constitute a layer as defined herein. The expression "disposed on" includes the case where the material is formed on a surface such that the material is in direct contact with the surface, as well as the case where the material is formed on a surface with one or more intervening materials between the disposed material and the surface. The insert material may constitute a layer as defined herein.

The optical film 14 can be formed using a variety of deposition methods, for example, vacuum deposition techniques such as chemical vapor deposition (e.g., plasma enhanced chemical vapor deposition, low pressure chemical vapor deposition, atmospheric pressure chemical vapor deposition, and plasma enhanced atmospheric pressure chemical vapor deposition), physical vapor deposition (e.g., reactive or non-reactive sputtering or laser ablation), thermal or electron beam evaporation, sputtering, and/or atomic layer deposition. One or more of the layers of optical film 14 may include nano-holes or a hybrid material to provide a particular range or value of refractive indices.

The thickness of the membrane 14 may range from about 0.005 μm to about 0.5 μm or from about 0.01 μm to about 20 μm. According to other examples, the thickness of the membrane 14 may be in the following range: about 0.01 μm to about 10 μm, about 0.05 μm to about 0.5 μm, about 0.01 μm to about 0.15 μm, or about 0.015 μm to about 0.2 μm. In other examples, the thickness of the film 14 may be about 100nm to about 200nm. The thickness of the thin film elements (e.g., crack deflection layer, crack mitigating layer, scratch resistant layer, film 14, discontinuous layer, spacing layer, bulk layer, first portion, second portion, third portion, etc.) is measured by Scanning Electron Microscopy (SEM) of cross-section or by ellipsometry (e.g., by n & k analyzer) or by thin film reflectometry. For multilayer components (e.g., crack mitigating stacks), the thickness is preferably measured by SEM.

The average and/or local optical or light transmission of the article 10 and/or film 14 in the visible wavelength band (e.g., about 500nm to about 800 nm) may be: greater than or equal to about 10% or greater, 20% or greater, 30% or greater, 40% or greater, 50% or greater 60% or greater, about 65% or greater, about 70% or greater, about 75% or greater, about 80% or greater, about 85% or greater, about 90% or greater, about 90.5% or greater, about 91% or greater, about 91.5% or greater, about 92% or greater, about 92.5% or greater, about 93% or greater, about 93.5% or greater, about 94% or greater, about 94.5% or greater, about 95% or greater, about 95.5% or greater, about 96% or greater, about 96.5% or greater, about 97% or greater, about 97.5% or greater, about 98% or greater, about 98.5% or greater, about 99.5% or greater, or about 99% or greater. The term "optical transmittance" refers to the amount of light transmitted through a medium. Optical transmittance measures the difference between the amount of light entering the medium and the amount of light leaving the medium. In other words, optical transmission is light that passes through a medium without being absorbed or scattered. The term "photopic average transmission" refers to the spectral average of the optical transmission multiplied by the luminous efficiency function, as defined by CIE standard observer. The optical transmission of the article 10 and/or film 14 may be measured according to American society for testing and materials standard D1003.

The article 10 and/or film 14 can have a haze of less than or equal to about 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, or less than or equal to about 1%. Similar to optical transmission, haze of the article 10 and/or film 14 may be measured according to American society for testing and materials standard D1003.

The article 10 and/or film 14 may have a low visible light reflectance. For example, the photopic average reflectance of the film 14 and/or article 10 over the visible wavelength region (e.g., about 500nm to about 800 nm) may be about 20% or less, about 10% or less, about 5% or less, about 4.5% or less, about 4% or less, about 3.5% or less, about 3% or less, about 2.5% or less, about 2% or less, about 1.5% or less, about 0.9% or less, about 0.5% or less, about 0.4% or less, or about 0.3% or less. As used herein, photopic reflectance simulates the human eye response, weighting the reflectance and wavelength spectrum according to the human eye sensitivity. Photopic reflectance may also be defined as the luminance or tristimulus Y value of the reflected light according to known specifications, such as the CIE color space specifications. The average photopic reflectance is defined by equation (1) as follows: spectral reflectance R (λ) multiplied by the color matching function of the light source spectrum (λ) and CIE

In relation to the spectral response of the eye,

in some cases, an article 10 including the film 14 can exhibit a color shift of about 10 or less, about 5 or less, or even the article exhibits a color shift of about 2 or less, when viewed under a light source at various incident illumination angles relative to normal incidence. In some cases, the color shift is about 1.9 or less, about 1.8 or less, about 1.7 or less, about 1.6 or less, about 1.5 or less, about 1.4 or less, about 1.3 or less, about 1.2 or less, about 1.1 or less, about 1.0 or less, about 0.9 or less, about 0.8 or less, about 0.7 or less, about 0.6 or less, about 0.5 or less, about 0.4 or less, about 0.3 or less, about 0.2 or less, or about 0.1 or less. In some embodiments, the color shift may be about 0. The light sources may include CIE-determined standard light sources including a-series light sources (representing tungsten filament illuminants), B-series light sources (representing simulated daylight light sources), C-series light sources (representing simulated daylight light sources), D-series light sources (representing natural daylight), and F-series light sources (representing various types of fluorescent illuminants). In a specific example, article 10 exhibits a color shift of about 2 or less when viewed with an incident illumination angle other than normal incidence under CIE F2, F10, F11, F12, or D65 light sources.

The range of incident illumination angles may be from normal incidence as: about 0 degrees to about 80 degrees, about 0 degrees to about 75 degrees, about 0 degrees to about 70 degrees, about 0 degrees to about 65 degrees, about 0 degrees to about 60 degrees, about 0 degrees to about 55 degrees, about 0 degrees to about 50 degrees, about 0 degrees to about 45 degrees, about 0 degrees to about 40 degrees, about 0 degrees to about 35 degrees, about 0 degrees to about 30 degrees, about 0 degrees to about 25 degrees, about 0 degrees to about 20 degrees, about 0 degrees to about 15 degrees, about 5 degrees to about 90 degrees, about 5 degrees to about 80 degrees, about 5 degrees to about 70 degrees, about 5 degrees to about 65 degrees, about 5 degrees to about 60 degrees, about 5 degrees to about 55 degrees, about 5 degrees to about 50 degrees, about 5 degrees to about 45 degrees, about 5 degrees to about 40 degrees, about 5 degrees to about 35 degrees, about 5 degrees to about 30 degrees, about 5 degrees to about 25 degrees, about 5 degrees to about 20 degrees, about 5 degrees to about 15 degrees, and all subranges therebetween.

The article 10 can exhibit the maximum color shift described herein at and along all incident illumination angles from about 0 degrees to about 80 degrees from normal incidence. In one example, the article can exhibit a color shift of 2 or less at any incident illumination angle in a range of about 0 degrees to about 60 degrees, about 2 degrees to about 60 degrees, or about 5 degrees to 60 degrees from normal incidence. The color shift is obtained by the following equation (2):

√((a* ₂ -a* ₁ ) ² +(b* ₂ -b* ₁ ) ² ) (2)

in the formula, a ₁ And b ₁ Is the color coordinate of the article when viewed at normal incidence, and a ₂ And b ₂ Is the color coordinates of the article 10 when viewed at an incident illumination angle. The color coordinates of the article 10 are either transmitted or reflected when viewed at both normal incidence and incident illumination angles.

According to various examples, the coated surface of the article 10 having the film 14 disposed thereon may exhibit a maximum hardness of about 8GPa or greater, about 9GPa or greater, about 10GPa or greater, about 11GPa or greater, about 12GPa or greater, about 13GPa or greater, about 14GPa or greater, about 15GPa or greater, about 16GPa or greater, about 17GPa or greater, about 18GPa or greater, as measured by berkovich nano-indentation at an indentation depth of about 100nm or greater. Hardness is measured by the "berkovich indenter hardness test," which involves indentation of a surface with a diamond berkovich indenter to measure the hardness of the material on the surface.

As used herein, the "maximum hardness value" of the film 14 is recorded as measured on an exterior surface (e.g., top surface or air surface) of the film 14 using a berkovich indenter hardness test, and the "maximum hardness value" of the film 14 is recorded as measured on the top surface of the film 14 (prior to application of additional layers or structures) using a berkovich indenter hardness test. More specifically, the hardness of the thin film coatings recorded herein were determined according to the berkovich indenter hardness test using widely accepted nanoindentation practice. See Fischer-Cripps, A.C. "Critical Review of Analysis and Interpretation of Nanoindentation Test Data", surface & Coatings Technology (2006), hereinafter "Fischer-Cripps" and Hay, J., agee, P and Herbert, E. "Continuous Stiffness measurement During instrumental Indentation Testing", experimental technologies, 34 (3) 86-94 (2010), hereinafter "Hay". For coatings, hardness and modulus are typically measured as a function of indentation depth. The properties of the coating can be separated from the resulting response profile as long as the coating is sufficiently thick. It should be appreciated that if the coating is too thin (e.g., less than about 500 nm), the coating properties may not be completely separated because they may be affected by close substrates having different mechanical properties. (see Hay). The method used to record the properties herein is representative of the coating itself. This procedure measures hardness and modulus as a function of depth of the emerging indentation to a depth of approximately 1000 nm. In the case of a hard coating on softer glass, the response curve will exhibit maximum levels of hardness and modulus at smaller indentation depths (less than or equal to about 200 nm). At deeper indentation depths, both hardness and modulus are progressively reduced, as the response is affected by the softer glass substrate. In this case, the coating hardness and modulus are taken from those associated with the zone exhibiting the greatest hardness and modulus. In the case of a soft coating on a harder glass substrate, the coating properties would exhibit the lowest hardness and modulus levels that occur at smaller indentation depths. At deeper indentation depths, the hardness and modulus will gradually increase as a result of the harder glass. These distributions of hardness and modulus versus depth can be obtained by using the conventional Oliver and Pharr methods (see Fischer-Cripps) or by the more efficient continuous stiffness method (see Hay).

For example, FIG. 11 shows a plot of the change in measured hardness values as a function of indentation depth and coating thickness. As shown in fig. 11, the hardness measured at the intermediate indentation depth (where the hardness is near and maintained at a maximum level) and at the deeper indentation depths depends on the thickness of the material or layer. FIG. 11 shows AlO with different thickness _x N _y The hardness response of the four different layers. The hardness of each layer was measured using a berkovich indenter hardness test. The 500nm thick layer exhibits its maximum hardness at an indentation depth of about 100nm to 180nm, followed by about 180nm to 180nmThe indentation depth hardness of about 200nm drops sharply, indicating that the hardness of the substrate influences the hardness measurement. A 1000nm thick layer exhibits a maximum hardness at indentation depths of about 100nm to about 300nm, followed by a sharp decrease in hardness at indentation depths greater than about 300 nm. The 1500nm thick layer exhibits a maximum hardness at an indentation depth of about 100nm to about 550nm, and the 2000nm thick layer exhibits a maximum hardness at an indentation depth of about 100nm to about 600 nm. While fig. 11 shows a thick monolayer, the same behavior is observed for thinner coatings and those that include multiple layers (e.g., film 14 of the embodiments described herein).

The elastic modulus and hardness values reported herein for such films were measured using the diamond nanoindentation method, as described above, with a berkovich diamond indenter tip.

According to various examples, the membrane 14 comprises: a first portion 14A disposed above a major surface 18A, one or more discontinuous layers 14B disposed above the first portion 14A, and a second portion 14C disposed above the one or more discontinuous layers 14B. It will be appreciated that the alternating structure of

portions

14A, 14C and discontinuous layer 14B may be repeated multiple times throughout the membrane 14. For example, the example of the film 14 in fig. 1B provides a third portion 14D over the second set of discontinuous layers 14B. The film 14 may also incorporate a plurality of impedance matching layers 22 and/or an anti-reflective layer 26. As understood in the art, the impedance matching layer 22 may be configured to reduce light reflection due to the film 14 back into the glass-based substrate 18. Each of the first portion 14A, the second portion 14C, and the third portion 14D may further include a body layer 30. Film 14 defines a film surface 14E disposed on the outer surface of antireflection film 26 or body layer 30. As explained in more detail below, the microstructure of the film 14 may be controlled or otherwise modified to adjust the roughness of the surface 14E. An easy-to-clean (ETC) coating 34 may be disposed on the surface 14E of the membrane 14. As explained in more detail below, the roughness of the control surface 14E may affect the durability of the ETC coating 34.

As shown in fig. 1A and 1B, the optical film 14 includes an antireflection coating 26, which may include multiple layers (26A, 26B). In one or more examples, anti-reflective coating 26 may include a period that includes two or more layers. In one or more examples, the two or more layers may be characterized as having different Refractive Indices (RI) from one another. According to various examples, the cycle includes a first low RI layer 26A and a second high RI layer 26B. The difference in refractive index between the first low RI layer and the second high RI layer can be about 0.01 or greater, 0.05 or greater, 0.1 or greater, or even 0.2 or greater. Antireflection layer 26 may include an additional cladding layer, which may include a lower index of refraction material than second high RI layer 26B.

Antireflective coating 26 may comprise multiple periods. A single period comprises a first low RI layer 26A and a second high RI layer 26B such that, when multiple periods are provided, the first low RI layer 26A and the second high RI layer 26B alternate in a repeating sequence such that the first low RI layer 26A and the second high RI layer 26B appear to alternate along the physical thickness of the antireflective coating 26. Antireflective coating 26 may comprise from about 1 to about 25 cycles, from about 2 to about 20 cycles, from about 2 to about 15 cycles, from about 2 to about 10 cycles, from about 2 to about 12 cycles, from about 3 to about 8 cycles, from about 3 to about 6 cycles.

In some examples, the cycle may include one or more third layers. The third layer may have a low RI, a high RI, or a medium RI. In some examples, the third layer may have the same RI as the first, lower RI layer 26A or the second, higher RI layer 26B. In other examples, the third layer may have a medium RI that is located between the RI of the first low RI layer 26A and the RI of the second high RI layer 26B. Alternatively, the third layer may have a refractive index greater than that of the second high RI layer 26B.

As used herein, the terms low "RI," "high RI," and "medium RI" refer to the relative values of RIs to each other (e.g., low RI < medium RI < high RI). In one or more examples, the term "low RI" when used with respect to the first low RI layer 26A or the third layer includes a range of about 1.3 to about 1.7 or to about 1.75. In one or more examples, the term "high RI" when used with respect to the second high RI layer 26B or the third layer includes a range of about 1.7 to about 2.5 (e.g., about 1.85 or greater). In some embodiments, the term "intermediate RI" when used for the third layer includes from about 1.55 to about 1.8. In some cases, the ranges of low, high, and medium RIs may overlap; however, in most cases, the layers of the antireflective coating 26 have the following general relationship for RI: low RI < medium RI < high RI.

Exemplary materials suitable for anti-reflective coating 26 include SiO ₂ 、Al ₂ O ₃ 、GeO ₂ 、SiO、AlO _x N _y 、AlN、SiN _x 、SiO _x N _y 、Si _u Al _v O _x N _y 、Ta ₂ O ₅ 、Nb ₂ O ₅ 、TiO ₂ 、ZrO ₂ 、TiN、MgO、MgF ₂ 、BaF ₂ 、CaF ₂ 、SnO ₂ 、HfO ₂ 、Y ₂ O ₃ 、MoO ₃ 、DyF ₃ 、YbF ₃ 、YF ₃ And/or CeF ₃ Wherein x, y, u, and v may be integers having a value of about 1 to about 10. Other examples of suitable materials for anti-reflective coating 26 include: polymers, fluoropolymers, plasma polymerized polymers, siloxane polymers, silsesquioxanes, polyimides, fluorinated polyimides, polyetherimides, polyethersulfones, polyphenylsulfones, polycarbonates, polyethylene terephthalate, polyethylene naphthalate, acrylic polymers, urethane polymers, polymethyl methacrylate, other materials cited below as suitable for use in the ETC coating 34, and other materials known in the art. Examples of some suitable materials for the first low RI layer 26A include: siO 2 ₂ 、Al ₂ O ₃ 、GeO ₂ 、SiO、AlO _x N _y 、SiO _x N _y 、Si _u Al _v O _x N _y 、MgO、MgAl ₂ O ₄ 、MgF ₂ 、BaF ₂ 、CaF ₂ 、DyF ₃ 、YbF ₃ 、YF ₃ And CeF ₃ . The nitrogen content of the material used for the first low RI layer 26A may be minimized (e.g., in a material such as Al) ₂ O ₃ And MgAl ₂ O ₄ Of (d) is used. Examples of some suitable materials for the second high RI layer 26B include: si _u Al _v O _x N _y 、Ta ₂ O ₅ 、Nb ₂ O ₅ 、AlN、Si ₃ N ₄ 、AlO _x N _y 、SiO _x N _y 、HfO ₂ 、TiO ₂ 、ZrO ₂ 、Y ₂ O ₃ 、Al ₂ O ₃ 、MoO ₃ Polycrystalline silicon, indium tin oxide, diamond, nanocrystalline diamond, and diamond-like carbon. The oxygen content of the material for the second high RI layer 26B can be minimized, particularly SiN _x Or AlN _x A material. AlO (aluminum oxide) _x N _y The material may be considered oxygen-doped AlN _x That is, they may have AlN _x The crystal structure (e.g., wurtzite) and does not necessarily have an AlON crystal structure.

As used herein, "AlO" in the present disclosure _x N _y ”、“SiO _x N _y "and" Si _u Al _x O _y N _z "materials include various aluminum oxynitride, silicon oxynitride, and silicon aluminum oxynitride materials, as understood by those skilled in the art of the present disclosure, described in terms of certain values and ranges for the subscripts" u "," x "," y ", and" z ". That is, it is usually expressed by "integer chemical formula" (e.g., al) ₂ O ₃ ) To describe the entity. Further, the expression "equivalent atomic ratio chemical formula" (e.g., al) is also generally employed _0.4 O _0.6 ) To describe an entity, which is equivalent to Al ₂ O ₃ . In the atomic ratio formula, the sum of all atoms in the formula is 0.4+0.6=1, and the atomic ratios of Al and O in the formula are 0.4 and 0.6, respectively. Many general textbooks describe atomic scale representations, and atomic scale representations are commonly used to describe alloys. See, for example: (i) Charles Kittel, "Introduction to Solid State Physics", seventh edition, john Wiley&Sons corporation, new york, 1996, pages 611-627; (ii) Smart and Moore, "Solid State Chemistry, an interaction, chapman&Hall University and Professional Division (Chapman, solid-state chemistry)&Introduction to Hall university and department of specialty) "london, 1992, pages 136-151; and (iii) James F. Shackelford "Introduction to Materials Science for Engineers (for industry)Introduction to materials science by stylists) ", sixth edition, the pilson apprentice Hall, new jersey (Pearson Prentice Hall), 2005, pages 404-418.

Refer again to "AlO" in the present disclosure _x N _y ”、“SiO _x N _y "and" Si _u Al _x O _y N _z "materials, subscripts, and the like enable one skilled in the art to treat these materials as a class of materials without specifying specific subscript values. In general, with respect to alloys, such as aluminum oxide, without specifying a particular subscript value, we may refer to it as Al _v O _x 。Al _v O _x Can represent Al ₂ O ₃ Or Al _0.4 O _0.6 . If the sum of v + x is chosen to be equal to 1 (i.e., v + x = 1), then the formula would be an atomic scale representation. Similarly, more complex mixtures may be described, e.g. Si _u Al _v O _x N _y Likewise, if the sum u + v + x + y is equal to 1, this will be the case for the atomic scale description.

Refer again to "AlO" in the present disclosure _x N _y ”、“SiO _x N _y "and" Si _u Al _x O _y N _z "materials," which symbols enable those skilled in the art to readily compare such materials with one another. That is, atomic ratio formulas are sometimes easier to use for comparison. For example, from (Al) ₂ O ₃ ) _0.3 (AlN) _0.7 Exemplary alloys of construction are closely equivalent to the formula describing Al _0.448 O _0.31 N _0.241 And also Al ₃₆₇ O ₂₅₄ N ₁₉₈ . Is composed of (Al) ₂ O ₃ ) _0.4 (AlN) _0.6 Another exemplary alloy of composition is closely equivalent to the formula describing Al _0.438 O _0.375 N _0.188 And Al ₃₇ O ₃₂ N ₁₆ . Atomic ratio of the formula Al _0.448 O _0.31 N _0.241 And Al _0.438 O _0.375 N _0.188 It is easier to compare with each other. For example, the atomic ratio of Al is reduced by 0.01O in the sub-ratio increased by 0.065 and N in the atomic ratio decreased by 0.053. More detailed calculations and considerations are needed to describe Al versus integer chemical formulas ₃₆₇ O ₂₅₄ N ₁₉₈ And Al ₃₇ O ₃₂ N ₁₆ . Thus, it is sometimes preferred to use the atomic ratio formula description of the entity. However, al is generally used _v O _x N _y As it includes any alloy containing Al, O and N atoms.

As will be understood by those skilled in the art of the present disclosure, for any of the foregoing materials (e.g., alN) of optical film 14, each subscript "u", "x", "y", and "z" may vary from 0 to 1, the sum of the subscripts may be less than or equal to 1, and the balance in the composition is the first element (e.g., si or Al) in the material. Furthermore, those skilled in the art will recognize that "Si" is a group of atoms _u Al _x O _y N _z "can be configured such that" u "is equal to 0, then the material can be described as" AlO _x N _y ". In addition, combinations where subscripts would result in pure elemental form (e.g., pure silicon, pure aluminum metal, oxygen, etc.) are excluded from the foregoing compositions for optical film 14. Finally, those skilled in the art will also recognize that the foregoing compositions may include other elements (e.g., hydrogen) not explicitly written out, which would result in a non-stoichiometric composition (e.g., siN _x With Si ₃ N ₄ ). Thus, the foregoing material of the optical film 14 may represent SiO ₂ -Al ₂ O ₃ -SiN _x -AlN or SiO ₂ -Al ₂ O ₃ -Si ₃ N ₄ Possible spaces in the AlN phase diagram, depending on the subscript value in the preceding composition representation.

In one or more examples, at least one layer of anti-reflective coating 26 may include a particular range of optical thicknesses. As used herein, the term "optical thickness" is determined by (n x d), where "n" refers to the RI of the sub-layer, and "d" refers to the physical thickness of the layer. In one or more examples, at least one layer of anti-reflective coating 26 may include an optical thickness of about 2nm to about 200nm, about 10nm to about 100nm, about 15nm to about 500nm, or about 15nm to about 5000nm. In some examples, all layers in anti-reflective coating 26 may have an optical thickness of about 2nm to about 200nm, about 10nm to about 100nm, about 15nm to about 500nm, or about 15nm to about 5000nm, respectively. In some cases, at least one layer of anti-reflective coating 26 has an optical thickness of about 50nm or greater. In some cases, the first low RI layer 26A may each have an optical thickness as follows: from about 2nm to about 200nm, from about 10nm to about 100nm, from about 15 to about 500nm, or from about 15 to about 5000nm. In other cases, the second high RI layer 26B may each have the following optical thicknesses: about 2nm to about 200nm, about 10nm to about 100nm, about 15 to about 500nm, or about 15 to about 5000nm.

In one or more examples, the physical thickness of anti-reflective coating layer 26 is about 800nm or less. The physical thickness of antireflective coating 26 can be in the following range: from about 10nm to about 800nm, from about 50nm to about 800nm, from about 100nm to about 800nm, from about 150nm to about 800nm, from about 200nm to about 800nm, from about 10nm to about 750nm, from about 10nm to about 700nm, from about 10nm to about 650nm, from about 10nm to about 600nm, from about 10nm to about 550nm, from about 10nm to about 500nm, from about 10nm to about 450nm, from about 10nm to about 400nm, from about 10nm to about 350nm, from about 10nm to about 300nm, from about 50 to about 300nm, and all ranges and subranges therebetween.

In some embodiments, antireflective coating 26 (and thus film 14) exhibits an average light reflectance of about 9% or less, about 8% or less, about 7% or less, about 6% or less, about 5% or less, about 4% or less, about 3% or less, or about 2% or less over the region of light wavelengths as measured at antireflective coating 26 alone (e.g., when reflection is removed from the uncoated back surface of article 10, such as by employing an index matching oil on the back surface in conjunction with an absorber, or other method). The average light reflectance (which may be a photopic average) may be in the following range: about 0.4% to about 9%, about 0.4% to about 8%, about 0.4% to about 7%, about 0.4% to about 6%, or about 0.4% to about 5%, and all subranges therebetween. In some cases, antireflective coating 26 may exhibit such average light reflectance over other wavelength ranges, for example, from about 420nm to about 650nm, from about 420nm to about 680nm, from about 420nm to about 700nm, from about 420nm to about 740nm, from about 420nm to about 850nm, or from about 420nm to about 950 nm. In some examples, antireflective coating 26 exhibits an average light transmission of about 90% or greater, 92% or greater, 94% or greater, 96% or greater, or 98% or greater over the region of light wavelengths. Unless otherwise specified, the average reflectance or transmittance is measured at incident illumination angles from about 0 degrees to about 10 degrees (however, such measurements may be provided at incident illumination angles of 45 degrees or 60 degrees).

Depending on various embodiments of the film 14 employing the discontinuous layer 14B, the discontinuous layer 14B may also be used to adjust roughness and provide high transmission for wavelengths outside the visible range (e.g., in the infrared or other wavelength ranges). The optical interference design of the discontinuous layer 14B may be adjusted to provide infrared transmission while controlling the microstructure of the film 14. For example, the film 14 may have a transmission of greater than 10%, greater than 20%, greater than 50%, or even greater than 80% for the infrared wavelength range of interest (e.g., about 750nm to about 2000nm, about 750 to about 950nm, about 900 to about 1200nm, about 1150nm to about 1400nm, about 1350nm to about 1650nm, about 1000nm to about 2000nm, and all ranges and subranges therebetween).

As explained above, in the example of a laminated article 10 including an antireflective coating 26, the surface 14E of the film 14 may be defined by the antireflective coating 26. Anti-reflective coating 26 may have substantially the same crystal structure and crystallite size as the bulk layer 30 on which anti-reflective coating 26 is disposed. Thus, it is advantageous to control the crystallite size of body layer 30 and thus of antireflection film 26. In examples where the laminated article 10 does not include an anti-reflective layer 26, the surface 14E on which the ETC coating 34 is disposed may be defined by one of the body layers 30.

The first, second and/or

third portions

14A, 14C, 14D may have a thickness of about 50nm to about 10 μm, or about 0.1 μm to about 5 μm, or about 0.1 μm to about 2 μm. The average and/or local optical or optical transmission of the first, second, and/or

third portions

14A, 14C, 14D in the visible wavelength band (e.g., about 500nm to about 800 nm) may be: greater than or equal to about 10% or greater, about 20% or greater, about 30% or greater, about 40% or greater, about 50% or greater, about 60% or greater, about 65% or greater, about 70% or greater, about 75% or greater, about 80% or greater, about 85% or greater, about 90% or greater, about 90.5% or greater, about 91% or greater, about 91.5% or greater, about 92% or greater, about 92.5% or greater, about 93% or greater, about 93.5% or greater, about 94% or greater, about 94.5% or greater, about 95%, about 95.5% or greater, about 96% or greater, about 96.5% or greater, about 97% or greater, about 97.5% or greater, about 98% or greater, about 98.5% or greater, about 99.5% or greater, or about 99% or greater. It will be appreciated that the transmissivity of the first, second and/or

third portions

14A, 14C, 14D may also be applied to the body layer 30 individually.

The body layer 30 of the first, second and/or

third portions

14A, 14C, 14D may comprise AlN _x 、AlO _x N _y 、AlN、Si ₃ N ₄ 、SiO _x N _y 、Si _u Al _v O _x N _y 、Al ₂ O ₃ 、ZrO ₂ Other optically transparent and rigid materials, and/or combinations thereof. It will be appreciated that u, x, y and v may be integers having a value of from about 1 to about 10. According to various examples, the material of body layer 30 may include a polycrystalline or semi-crystalline crystal structure. It will be understood that the body layers 30 may each comprise the same or different materials as the other body layers 30. For example, the first, second and

third portions

14A, 14C, 14D of the membrane 14 can include a composition comprising AlO _x N _y Wherein x (representing the mole fraction of oxygen relative to aluminum) is from about 0.02 to about 0.25; and wherein y (representing the mole fraction of nitrogen relative to aluminum) is from about 0.75 to about 0.98.

Body layer 30 may have the following thicknesses: about 100nm or greater, about 200nm or greater, about 300nm or greater, about 400nm or greater, about 500nm or greater, about 600nm or greater, about 700nm or greater, about 800nm or greater, about 900nm or greater, about 1000nm or greater, about 1100nm or greater, about 1200nm or greater, about 1300nm or greater, about 1400nm or greater, or about 1500nm or greater. The body layer 30 can have the same thickness or different thicknesses, respectively. According to various examples, body layer 30 may constitute a portion of, a majority of, or substantially all of first, second, and

third portions

14A, 14C, 14D. For example, body layer 30 may constitute about 10% or more, about 20% or more, about 30% or more, about 40% or more, about 50% or more, about 60% or more, about 70% or more, about 80% or more, about 90% or more, about 95% or more, or about 99% or more of the total thickness of first, second, and

third portions

14A, 14C, 14D.

According to various examples, one or more of the body layers 30 are in contact with at least one of the discontinuous layers 14B. The membrane 14 may include a single or multiple discontinuous layers 14B. The discontinuities 14B may be uniformly or non-uniformly distributed throughout the membrane 14, or may be grouped. In the illustrated example, the discontinuous layers 14B are arranged in groups, or in groups of 3, with a spacing layer 38 between the discontinuous layers 14B. It will be appreciated that examples of groupings of the discontinuous layers 14B may include 2, 4, 5, 6, 7, 8, 9, 10 or more discontinuous layers 14B without departing from the teachings provided herein.

The spacer layer 38 may have the following thicknesses: about 100nm or less, 90nm or less, 80nm or less, 70nm or less, 60nm or less, 50nm or less, 40nm or less, 30nm or less, 20nm or less, 10nm or less, 9nm or less, 8nm or less, 7nm or less, 6nm or less, 5nm or less, 4nm or less, 3nm or less, 2nm or less, or 1nm or less. The spacer layer 38 may comprise AlN _x 、AlO _x N _y 、AlN、Si ₃ N ₄ 、SiO _x N _y 、Si _u Al _v O _x N _y 、ZrO ₂ 、Al ₂ O ₃ 、SiO ₂ And/or combinations thereof. It will be appreciated that x, y, u and v may be integers having a value of from about 1 to about 10. Although shown as including a single spacing layer 38 separating the discontinuous layers 14B, it will be understood that each spacing layer 38 may include several sub-layers and/or that multiple spacing layers 38 separate the discontinuous layers 14B.

According to various examples, one or more of the discontinuous layers 14B may have a different microstructure than the first, second, and

third portions

14A, 14C, 14D. For example, the first, second, and

third portions

14A, 14C, 14D may have crystalline, polycrystalline, and/or semi-crystalline microstructures, while one or more of the discontinuous layers 14B may have a different crystalline, polycrystalline, semi-crystalline, porous, and/or amorphous microstructure. Such features may be advantageous for reducing the average grain or crystallite size of the bulk layer 30 grown on top of the discontinuous layer 14B. For example, by forming, depositing, and/or growing one of body layers 30 on one of discontinuous layers 14B, the microstructural differences of discontinuous layer 14B relative to body layer 30 may result in fine grain sizes of polycrystalline and/or semi-crystalline instances of body layer 30. Using the discontinuous layer 14B to separate the bulk layer 30 of each

portion

14A, 14C, 14D may reduce the average crystallite size at the surface 14E of the film 14.

According to various examples, the mechanical properties of the discontinuous layer 14B may be different from the body layer 30 and/or the first, second, and

third portions

14A, 14C, 14D (e.g., due to microstructure and/or material differences). Thus, the mechanical properties of the article 10 may be controlled by the selection of the microstructure of the discontinuous layer 14B. For example, if the discontinuous layer 14B is configured to have a porous microstructure having a lower mechanical strength than the first, second, and

third portions

14A, 14C, 14D, the discontinuous layer 14B may function as a crack deflection layer, which may alter the fracture behavior of the article 10.

Discontinuous layer 14B may have a thickness as follows: about 100nm or less, 90nm or less, 80nm or less, 70nm or less, 60nm or less, 50nm or less, 40nm or less, 30nm or less, 20nm or less, 10nm or less, 9nm or less, 8nm or less, 7nm or less, 6nm or less, 5nm or less, 4nm or less, 3nm or less, 2nm or less, or 1nm or less. According to another example, one or more of the discontinuous layers 14B may have a thickness as follows: about 1nm or greater, about 2nm or greater, about 3nm or greater, about 4nm or greater, about 5nm or greater, about 6nm or greater, about 7nm or greater, about 8nm or greater, about 9nm or greater, about 10nm or greater, about 20nm or greater, about 30nm or greater, about 40nm or greater, or about 50nm or greater. The thicknesses of the discontinuities 14B may all be the same or different. Since the discontinuous layer 14B may be thin relative to the bulk layer 30 of the membrane 14, the discontinuous layer 14B may occupy about 20% or less, about 19% or less, about 18% or less, about 17% or less, about 16% or less, about 15% or less, about 14% or less, about 13% or less, about 12% or less, about 11% or less, about 10% or less, about 9% or less, about 8% or less, about 7% or less, about 6% or less, about 5% or less, about 4% or less, about 3% or less, about 2% or less, or about 1% or less of the total thickness of the membrane 14 or any of the first, second, and/or

third portions

14A, 14C, 14D, individually or as a whole. Since the discontinuous layer 14B occupies a lower overall thickness of the film 14, the optical and/or mechanical properties of the body layer 30 may dominate the optical and/or mechanical properties of the film 14. In other words, the thinness of the discontinuous layer 14B allows the body layer 30 to dominate the optical and/or mechanical properties of the film 14.

As explained above, the discontinuous layer 14B may comprise a material having a microstructure different from that of the body layer 30. The discontinuous layer 14B may include a metal, an insulator (insulator), and/or a carbonaceous material (e.g., amorphous carbon, DLC, C-70, and/or a graphite material) and may also employ a carbide film (e.g., tungsten carbide or SiC). According to some examples, the discontinuous layer 14B may comprise a thin metal film, such as W and/or Mo. According to other examples, non-metallic materials may be used for the discontinuous layer 14B, such as: al (aluminum) ₂ O ₃ 、TiO ₂ 、SiO ₂ 、Nb ₂ O ₅ 、SiOC、SiN _x 、AlN _x And Y ₂ O ₃ -ZrO ₂ . Other oxides, nitrides, or oxycarbides may also be employed in the discontinuous layer 14B. The discontinuous layer 14B may be applied to the body layer 30 via electrostatic deposition and/or any of the methods described above in connection with the film 14. Such as Al ₂ O ₃ Such materials may be crystalline or amorphous depending on the film deposition process, plasma energy, ionization, and temperature. In some cases, the discontinuous layer 14B may have the same chemical composition as the bulk layer 30, but by being in the same layer as the bulk layerUsing variations in the deposition process, the density and/or crystallinity of bulk layer 30 may be higher than that of discontinuous layer 14B (i.e., a different microstructure). Amorphous Al of the discontinuous layer 14B may be formed by a reactive sputtering process ₂ O ₃ And SiO ₂ Examples of films.

The refractive index of the discontinuous layer 14B may be significantly different (e.g., having about 0.1 index unit difference or greater, about 0.5 index unit difference or greater, about 1.0 index unit difference or greater) than the bulk layer 30 of the first, second and/or

third portions

14A, 14C, 14D, while still maintaining very high optical transmission through the layer design. For example, at a wavelength of 550nm, the refractive index difference of the discontinuous layer 14B relative to the body 30 and/or the spacing layer may be about 0.12 or greater, 0.15 or greater, 0.2 or greater, 0.3 or greater, or 0.4 or greater. The average and/or local optical or light transmission of the discontinuous layer 14B in the visible wavelength band (e.g., about 450nm to about 650 nm) may be: about 10% or more, about 20% or more, about 30% or more, about 40% or more, about 50% or more, about 60% or more, about 65% or more, about 70% or more, about 75% or more, about 80% or more, about 85% or more, about 90% or more, about 90.5% or more, about 91% or more, about 91.5% or more, about 92% or more, about 92.5% or more, about 93% or more, about 93.5% or more, about 94% or more, about 94.5% or more, about 95%, about 95.5% or more, about 96% or more, about 96.5% or more, about 97% or more, about 97.5% or more, about 98% or more, about 98.5% or more, about 99.5% or more, or about 99% or more. The refractive index contrast of the discontinuous layer 14B with the bulk layer 30 may be generally high, requiring careful optical design and layer thickness control to achieve the desired optical transmission.

As explained above, the discontinuous layer 14B is configured to modify the crystal growth behavior of the bulk layer 30 of the first, second and/or

third portions

14A, 14C, 14D. For example, with the bulk layer 30 (e.g., polycrystalline and/or semi-crystalline Al) of the first portion 14A ₂ O ₃ 、ZrO ₂ Or AlO _x N _y ) Growth and/or deposition (e.g. ofBy vapor deposition), the bulk layer 30 undergoes grain coarsening of the bulk layer 30. In other words, bulk layer 30 is initially of a fine grain size, and as the deposition of bulk layer 30 continues, the crystal grains grow in columnar directions and become larger, thereby encasing the other smaller crystals. If left unchecked, the surface of the film 14 may exhibit high roughness due to the presence of large crystals or coarse grains of crystals. Such results may be disadvantageous because as a result, films, coatings, and layers applied to the rough surface of the film 14 may exhibit the same roughness and degraded mechanical properties (high friction, poor wear tolerance, etc.). Thus, by introducing a discontinuous layer 14B having a microstructure different from that of the body layer 30, the growth of large crystals can be blocked, disturbed or reset. The blocking or resetting of the growth sites of the bulk layer 30 achieves that the grain size of the bulk layer 30 starts again from fine grains. The use of the discontinuous layer 14B may achieve that the second or

third portions

14C, 14D of the film 14 within about 100nm from the discontinuous layer 14B have an average microstructured crystal size that is less than the average microstructured crystal size of the first portion 14A within about 100nm from the discontinuous layer 14B. Fine grain structure can be achieved while retaining other product or process advantages such as high hardness, high toughness, high film density, high optical transmission, or high deposition rate of the film 14.

The use of the discontinuous layer 14B may reduce the final particle or crystallite size of the body layer 30 and/or the anti-reflective coating 26. Such a reduction in average particle size may result in a surface roughness low enough to minimize the impact on the ETC coating 34. At the microscopic level or lower, "roughness", "average surface roughness (Ra)" or similar terms refer to an uneven or irregular surface condition, such as average Root Mean Square (RMS) roughness (Rq). Ra is calculated as the average roughness of the microscopic peaks and valleys of the surface measurement. Rq is calculated as RMS of the microscopic peak valley measured at the surface. When described as Rq, the roughness can be about 20 nanometers or less, about 19nm or less, about 18nm or less, about 17nm or less, about 16nm or less, about 15nm or less, about 14nm or less, about 13nm or less, about 12nm or less, about 11nm or less, about 10nm or less, about 9nm or less, about 8nm or less, about 7nm or less, about 6nm or less, about 5nm or less, about 4nm or less, about 3nm or less, about 2nm or less, or about 1nm or less. When described as Ra, the roughness can be about 20nm or less, about 19nm or less, about 18nm or less, about 17nm or less, about 16nm or less, about 15nm or less, about 14nm or less, about 13nm or less, about 12nm or less, about 11nm or less, about 10nm or less, about 9nm or less, about 8nm or less, about 7nm or less, about 6nm or less, about 5nm or less, about 4nm or less, about 3nm or less, about 2nm or less, or about 1nm or less.

Placed on top of the antireflective layer 26 of the second and

third portions

14C, 14D of the film 14 is an ETC coating 34. According to various examples, the ETC coating 34 includes a fluorinated material (e.g., a perfluoropolyether (PFPE) silane, a perfluoroalkyl ether, a PFPE oil, or other suitable fluorinated material). According to some examples, the ETC coating 34 is about 1nm to about 20nm thick. In other aspects, the ETC coating 34 has a thickness in a range from 1nm to about 200nm, from 1nm to about 100nm, and from 1nm to about 50nm. In some examples, the ETC coating 34 may have a thickness of about 0.5nm to about 50nm, about 1nm to about 25nm, about 4nm to about 25nm, or about 5nm to about 20nm. In other examples, the ETC coating 34 may be about 10nm to about 50nm thick.

A variety of source materials may be used to form the ETC coating 34.ETC coating source materials may include: perfluoropolyether (PFPE) silanes, perfluoropolyether (PFPE) alkoxysilanes, copolymers of these PFPEs, and mixtures of these PFPEs. For example, the ETC coating 34 may include a chemical formula [ CF ] ₃ CF ₂ CF ₂ O) _a ] _y SiX _4-y Wherein a is 5 to 50, y =1 or 2, and X is-Cl, acetoxy, -OCH ₃ Or OCH ₂ H ₃ Wherein the total chain length of the chain-end perfluoropolyethers from the silicon atom to its maximum length is from 6 to 130 carbon atoms. In other aspects, "a" in the above formula can range from about 10 to 30. Further, it should be understood that the above PFPE formula is one of many suitable PFPE types suitable for the ETC coating 34 of the present disclosure; thus, it is used as an exemplary chemicalProvided, is not intended to limit in any way the chemical formula or mixture of chemical formulas suitable for the ETC coating 34 of the present disclosure. Thus, other PFPEs having structural changes in perfluoropolyether chains and/or attachment chemistries relative to the exemplary forms provided above can be employed in the ETC coating 34. For example, optool from Daikin industries, inc. (Daikin industries) ^TM UF503 fluorinated coating is another suitable PFPE that may be used for the ETC coating 34. As used herein, the length unit of a carbon chain is nanometers, which is the product of the number of carbon-carbon bonds along the maximum length of the chain multiplied by the length of a single carbon-carbon bond of 0.154 nm. In some examples, the carbon chain length of the perfluoropolyether (PFPE) group can range from about 0.1nm to about 50nm, from about 0.5nm to about 25nm, or from about 1nm to about 20nm.

Further, as described above, examples of the ETC coating 34 may include PFPE oil. According to some examples, the PFPE oil used for ETC coating 34 may be dissolved in the ETC component that is directly bonded to optical film 14. Generally, PFPE oils are characterized by oxidation resistance. In other aspects, the PFPE oil of the ETC coating 34 is a discrete layer disposed on the ETC component directly bonded to the optical film 14 and/or the body layer 30. In other aspects, the PFPE oil of the ETC coating 34 is a combination of dissolved and discrete layers. According to some examples, PFPE oils for ETC coating 34 may include: solvay from Chemours Company

Z-type oil,

Y-type oil,

K type oil, krytox ^TM Type K oil, demnum from Dajin industries ^TM Type oil, or other similar PFPE oil.

According to various examples, the ETC coating 34 is characterized by high durability. Thus, some examples of exposed surfaces of the ETC coating 34 have an average water contact angle of 70 ° or greater after being subjected to 2000 reciprocating cycles at a load of 1kg, according to the steel wool test (i.e., as described below). According to the steel wool test, the exposed surface of the ETC coating 34 may also include an average water contact angle of 70 ° or greater after being subjected to 3500 cycles of reciprocation at a load of 1 kg. In other aspects, according to the steel wool test, the exposed surface of the ETC coating 34 retains an average water contact angle of 70 ° or greater, 75 °, 80 °, 85 °, 90 °, 95 °, 100 °, 105 °, 110 °, or 115 ° (including all average contact angles between these levels) after 2000 or 3500 such cycles.

As used herein, a "steel wool test" is a test used to determine the durability of the ETC coating 34 disposed on a glass, glass-ceramic, or ceramic substrate (e.g., glass-based substrate 18) used in an article of the present disclosure. At the beginning of the steel wool test, the water contact angle is measured one or more times on a particular sample to obtain a reliable initial water contact angle. These water contact angle measurements are performed using a Kruss GmbH DSA100 drop analyser or similar instrument. After measuring the initial water contact angle, a Bonstar #0000 steel wool pad was fixed to

Industrial 5750 arm of linear grinder instrument. The steel wool pad was then brought into contact with the sample (on the ETC coating 34) under a 1kg load and set at 60 cycles/min. The average contact angle of the sample is then measured after 2000 cycles, 3500 cycles, and/or other specified durations.

According to various examples, the article 10 may have a haze of less than or equal to about 5% through the ETC coating 34 and the glass, glass-ceramic, or ceramic substrate 18. In certain aspects, the haze through the ETC coating 34 and the glass-based substrate 18 is equal to or less than 5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.75%, 0.5%, or 0.25% or less (including all haze levels between these levels). In other instances, examples of the article 10 incorporate appreciable haze (> 5%) as part of its functionality, and also include an ETC coating 34 having high durability (e.g., having an average water contact angle of 100 degrees or greater after being subjected to 2000 cycles or 3500 cycles under a 1kg load, according to the steel wool test). As used herein, the "haze" attributes and measurements recorded in the present disclosure are measurements with or in any other way based on a BYK-gardner haze meter using an aperture of a source port of about 7mm diameter.

The ETC coating 34 may be applied to or disposed on the membrane 14 in various ways. According to some examples, ETC coating 34 may be deposited by various methods, including but not limited to spray coating, dip coating, spin coating, and vapor deposition. Vapor deposition protocols for depositing the ETC coating 34 may include, but are not limited to: physical vapor deposition ("PVD"), electron beam deposition ("e-beam" or "EB"), ion assisted deposition EB ("IAD-EB"), laser ablation, vacuum arc deposition, thermal evaporation, sputtering, plasma Enhanced Chemical Vapor Deposition (PECVD), and other similar vapor deposition techniques.

According to various examples, the optical film 14 may also include a crack mitigating layer. This crack mitigating layer may inhibit or prevent crack bridging between the film 14 and the substrate 18, thereby modifying or improving the mechanical properties or strength of the article 10. Embodiments of the crack mitigating layer are further described in U.S. patent application Ser. Nos. 14/052,055, 14/053,093, and 14/053,139, which are incorporated herein by reference. The crack mitigating layer may comprise a crack passivating material, a crack deflecting material, a crack trapping material, a tough material, or a controlled adhesion interface. The crack mitigating layer may comprise a polymeric material, a nanoporous material, a metal oxide, a metal fluoride, a metallic material, or other materials mentioned herein for the membrane 14. The structure of the crack mitigating layer may be a multilayer structure, wherein the multilayer structure is designed to deflect, inhibit or prevent crack propagation. The crack mitigating layer may comprise a nanocrystallite, a nanocomposite, a phase change toughening material, a multilayer of organic materials, a multilayer of inorganic materials, a multilayer of alternating organic and inorganic materials, or a hybrid organic-inorganic material. The crack mitigating layer may have a strain to failure of greater than about 2% or greater than about 10%. These crack mitigating layers may also be combined with the substrate 18 or the film 14 alone. As noted above, in some cases, the mechanical properties of the discontinuous layers 14B may also be engineered such that they act as crack mitigating layers or crack deflecting layers.

The crack mitigating layer may comprise tough or nano-microstructured minerals such as: zinc oxide, certain Al alloys, cu alloys, steel or stabilized tetragonal zirconia (including phase change toughened, partially stabilized, yttria stabilized, ceria stabilized, calcia stabilized and magnesia stabilized zirconia); zirconia toughened ceramics (including zirconia toughened alumina); a ceramic-ceramic composite; a carbon-ceramic composite; fibre-or whisker-reinforced ceramics or glass-ceramics (e.g. SiC or Si) ₃ N ₄ Fiber or whisker reinforced ceramics); a metal-ceramic composite; porous or non-porous hybrid organic-inorganic materials, such as nanocomposites, polymer-ceramic composites, polymer-glass composites, fiber-reinforced polymers, carbon nanotube or graphene-ceramic composites, silsesquioxanes, polysilsesquioxanes, or "ORMOSILs" (organically modified silica or silicates), and/or various porous or non-porous polymeric materials, such as: silicones, polysiloxanes, polyacrylates, polyacrylics, PI (polyimides), fluorinated polyimides, polyamides, PAI (polyamideimides), polycarbonates, polysulfones, PSU or PPSU (polyarylsulfones), fluoropolymers, fluoroelastomers, lactams, polycycloolefins, and similar materials, including but not limited to: PDMS (polydimethylsiloxane), PMMA (poly (methyl methacrylate)), BCB (benzocyclobutene), PEI (polyethyletherimide), poly (arylene ether) s, for example: PEEK (polyetheretherketone), PES (polyethersulfone) and PAR (polyarylate), PET (polyethylene terephthalate), PEN (polyethylene naphthalate = poly (ethylene-2, 6-naphthalene dicarboxylate)), FEP (fluorinated ethylene propylene), PTFE (polytetrafluoroethylene), PFA (perfluoroalkoxy polymer, for example, under the trade name PEEK (poly ether ketone)), PFA (poly (arylene ether)), and a polymer thereof

) And the like. Other suitable materials include modified polycarbonate, versions of epoxy, cyanate ester, PPS (polyphenyl sulfide (p)olyphenylsulfides), polyphenylenes, polypyrrolones, polyquinoxalines and bismaleimides.

According to various examples, an exemplary method of forming film 14 or a functional coating on substrate 18 may include the steps of: the first portion 14A is deposited on the major surface 18A of the substrate 18. As explained above, the first portion 14A may be deposited in a variety of ways, including chemical vapor deposition (e.g., plasma enhanced chemical vapor deposition, low pressure chemical vapor deposition, atmospheric pressure chemical vapor deposition, and plasma enhanced atmospheric pressure chemical vapor deposition), physical vapor deposition (e.g., reactive or non-reactive sputtering or laser ablation), thermal or electron beam evaporation, sputtering, and/or atomic layer deposition. Next, a step of depositing one or more discontinuous layers 14B on first portion 14 is performed, the discontinuous layer 14B comprising a microstructure different from first portion 14A and having an optical transmission greater than about 85% over the visible wavelength range of about 450nm to about 650 nm. As explained above, the discontinuous layer may be amorphous, crystalline, or any other microstructure different from the microstructure of the body layer 30 of the first portion 14A. Next, a step of depositing a second portion 14B over the one or more interrupted layers 14B is performed. Such steps may include depositing additional body layers 30. The method may further include the step of depositing the one or more discontinuous layers 14B to have a thickness of about 100nm or less. As explained above, the discontinuous layer 14B may have a thickness as follows: about 100nm or less, 90nm or less, 80nm or less, 70nm or less, 60nm or less, 50nm or less, 40nm or less, 30nm or less, 20nm or less, 10nm or less, 9nm or less, 8nm or less, 7nm or less, 6nm or less, 5nm or less, 4nm or less, 3nm or less, 2nm or less, or 1nm or less. It will be understood that the steps of the methods may be performed in any order, and that steps may be removed and/or added without departing from the teachings provided herein.

Referring now to fig. 2, the article 10 may be integrated into an electronic product 50. Although shown as a mobile phone, the electronic product 50 may be a tablet, a portable music device, a television, a computer monitor, or any type of electronic product 50 that may display information (e.g., video, pictures, etc.) in a pattern. The electronic product 50 includes a housing 54 having a front surface, a back surface, and side surfaces. The electronic components are at least partially disposed in the housing 54. The electronic components may include at least a controller, a memory, and a display. The display may be located at or adjacent the front surface of the housing 54. A cover glass 58 is disposed over the display. According to various examples, a portion of the housing 54 or the cover glass 58 comprises the article 10 as described herein.

Various advantages may be provided using the present disclosure. First, the use of the discontinuous layer 14B achieves a polycrystalline or semi-crystalline body layer 30 with controlled crystallite size or controlled surface roughness while maintaining high hardness, high optical transmission, and low color shift. As explained above, the low roughness provided by the controlled crystallite size of the body layer 30 may increase the mechanical durability of the ETC layer 34 by providing a smooth surface for applying the ETC coating 34. Second, the discontinuous layer 14B may comprise the same or similar materials used for the bulk layer 30, which may allow for simplified processing and formation of the discontinuous layer 14B in situ in the same deposition chamber as the bulk layer 30. Benefits of low roughness may include: low friction, enhanced wear properties, low heat generation due to friction, enhanced sliding, high cleanability, and enhanced bonding, among others.

The following examples represent certain non-limiting examples of the present disclosure.

Examples

Referring now to fig. 3-10B, various optical coatings (e.g., films 14) having a modified layer (e.g., discontinuous layer 14B) have been modeled and formed to have similar or consistent nanoindentation hardness as compared to a similar hard coating without the modified layer. Without being bound by theory, it is believed that similar or consistent nanoindentation hardness indicates that a hard coating with a modification layer such as described herein can be fabricated with scratch resistance, damage resistance, toughness, and spallation behavior similar to a hard coating without a modification layer.

AlO production by reactive sputtering _x N _y 、Al ₂ O ₃ And SiO ₂ A film, and measuring the resulting refractive index using spectroscopic ellipsometry. These refractive index profiles were used in an optical transfer matrix model to design transparent modification layers and bulk hard coatings and scratch-resistant anti-reflective coating structures modeled in the examples provided below. Optical modeling was also used to design the target coating thickness for examples 5 and 6. The modified layer modeled here was designed to: is thin (e.g., each layer is about 100nm or less, in some cases about 50nm or less or about 25nm or less); is amorphous or has a crystalline structure different from that of the bulk hardcoat material (e.g., body layer 30); and optically transparent by layer thickness design or by closely matching the refractive index of the hard coat material.

The graphs of fig. 3-10B show various modeled optical properties for different coating embodiments. It will be seen that the optical properties (e.g., reflectance and transmittance) of comparative examples 1 and 2, which do not include a modification layer, are not significantly different from examples 1, 2, 3 and 4, which contain a modification layer. Each of the modified layers of examples 1, 2, 3 and 4 contained Al ₂ O ₃ . Thus, the optical properties of the optical coating embodiments are not significantly altered by the modifying layer. Tables 1, 2 and 3 provide an abbreviated list of refractive indices of materials used in the optical modeling of comparative examples 1 and 2 and examples 1-4.

Table 1: alO (aluminum oxide) _x N _y Thick, alO _x N _y List of refractive indices of thin sum A1ON-57

Table 2: al (Al) ₂ O ₃ And Al ₂ O ₃ List of refractive indices of RS

Table 3: siO 2 ₂ And SiO ₂ List of refractive indices of-56

Table 4: concrete design of comparative example 1

		Refractive index	Physical thickness
				Layer(s)	Material	Refractive index at 550nm	Thickness (nm)
Medium	Air (a)	1
				10	SiO ₂ -56	1.481	45
9	A1ON-57	2.006	39
				8	SiO ₂ -56	1.481	11
7	A1ON-57	2.006	2000
				6	SiO ₂ -56	1.481	8.9
5	A1ON-57	2.006	42.6
				4	SiO ₂ -56	1.481	30.1
3	A1ON-57	2.006	24.5
				2	SiO ₂ -56	1.481	52.4
1	A1ON-57	2.006	7.7
				Base material	5318 glass	1.5054
Total thickness of			2261.2

Table 5: specific design of example 1

Table 6: concrete design of example 2

Table 7: concrete design of comparative example 2

Table 8: specific design of example 3

Table 9: specific design of example 4

As can be seen from FIGS. 3-10B, the incorporation of a modifying layer (e.g., comprising Al) in the layered structure of an optical coating (e.g., film 14) as compared to an optical coating that does not incorporate a modifying layer ₂ O ₃ Does not significantly change the reflectivity, transmissivity, and/or reflected or transmitted color of the optical coating.

In addition to the optical model of the exemplary coating, a number of coating examples were also experimentally produced to demonstrate the effectiveness of using the modified layer. In a Danton (Denton) sputtering tool, in DC mode, using an Al target, the contents of N, ar and Ar +5% ₂ Experimental examples were produced as process gases. Al deposition at 14 mTorr pressure, 421V and 0.47kW ₂ O ₃ . The process gas is 95% Ar/5% O fed into the chamber at 50sccm ₂ . AlO deposition at 2 mTorr pressure, 295V and 0.40kW _x N _y The processing gas Ar is set to 15sccm and N ₂ Was set to 15sccm. 2-3% of the residual oxygen due to the residual oxygen and water in the chamberIncorporated into the membrane (analyzed by XPS). Comparative example 3 is an optical coating that does not include a modifying layer, while examples 5 and 6 include multiple modifying layers (e.g., including Al) ₂ O ₃ The layer(s).

Table 10: concrete design of comparative example 3 produced

Layer(s)	Material	Thickness (nm)
			1	AlO _X N _Y	1000
Substrate material	Glass

Table 11: specific design of example 5 for experimental manufacture

Layer(s)	Material	Thickness (nm)
			7	AlO _X N _Y	430
6	Al ₂ O ₃	5
			5	AlO _X N _Y	59.5
4	Al ₂ O ₃	5
			3	AlO _X N _Y	59.5
2	Al ₂ O ₃	5
			1	AlO _X N _Y	430
Base material	Glass

Table 12: specific design of example 6 for experimental fabrication

Comparative example 3, which did not have the bond modification layer, had an average Rq of 5.1nm, an average Ra of 4.1nm, an elastic modulus of 199GPa, and a hardness of 14.6 GPa. Comparative example 3 contains mainly polycrystalline AlO _x N _y (in this case, alN) _x Doped with about 3 atomic% oxygen). Example 5, which incorporates 3 modified layers, had an average Rq of 3.6nm, an average Ra of 2.9nm, an elastic modulus of 190GPa, and a hardness of 14.5 GPa. Example 6 incorporating 4 modified layers had an average Rq of 3.5nm, an average Ra of 2.8nm, an elastic modulus of 215GPa, and a hardness of 16 GPa. These examples experimentally demonstrate the concept of reducing roughness, controlling microstructure, and maintaining hardness by inserting a very thin optically engineered amorphous (in this case, semi-porous) modification layer (e.g., discontinuous layer 14B).

Claims

1. A coated article, comprising:

a glass, glass-ceramic or ceramic substrate comprising a major surface; and

a functional coating disposed on a major surface of the substrate, the functional coating comprising:

a first portion disposed on the major surface;

one or more discontinuous layers disposed on the first portion; and

a second portion disposed over the one or more discontinuous layers,

wherein the one or more discontinuous layers are configured such that the crystal growth behavior of the first portion and/or the second portion is altered, the one or more discontinuous layers comprise a microstructure that is different from the microstructure of the first portion, and the functional coating has an average optical transmission of greater than 10% over the visible wavelength range of 450nm to 650nm, the first portion and the second portion comprise the same material, and the second portion within 100nm of the functional coating from the discontinuous layer comprises an average microstructured crystal size that is less than the average microstructured crystal size of the first portion within 100nm from the discontinuous layer.

2. The coated article of claim 1, wherein the one or more discontinuous layers comprise a microstructure different from both the first and second portions.

3. The coated article of claim 1, wherein the one or more discontinuous layers have an amorphous microstructure.

4. The coated article of claim 1, wherein the first and second portions of the coating each comprise multiple layers, and the coating has an average optical transmission of greater than 50%.

5. The coated article of any one of claims 1-4, wherein each of the one or more discontinuous layers comprises a thickness of 50nm or less.

6. The article of claim 5, wherein the one or more discontinuous layers comprise a thickness of 10nm or less.

7. The article of any one of claims 1-4, wherein the one or more discontinuous layers are porous.

8. The article of any one of claims 1-4, wherein at least one of the first and second portions comprises a thickness of 0.1 μm to 2 μm.

9. The article of any one of claims 1-4, wherein the one or more discontinuous layers comprise three layers, and the article further comprises a plurality of spacing layers between the one or more discontinuous layers.

10. The article of any one of claims 1-4, further comprising:

an easy-to-clean (ETC) coating disposed on the second portion of the functional coating.

11. The article of any one of claims 1-4, wherein the coating comprises a surface roughness of 5nm Rq or less.

12. A coated article, comprising:

a substrate comprising a major surface and comprising a glass, glass-ceramic, or ceramic composition; and

a functional coating disposed on a major surface of a substrate to form a coated surface, the functional coating comprising:

a first portion disposed on the major surface;

a plurality of discontinuous layers disposed over the first portion, the plurality of discontinuous layers comprising a microstructure different from the microstructure of the first portion; and

a second portion disposed over the plurality of discontinuous layers,

wherein the plurality of discontinuous layers are configured such that the crystal growth behavior of the first portion and/or the second portion is altered, the plurality of discontinuous layers comprises an optical transmission of greater than 85% over a visible wavelength range of 450nm to 650nm, and each of the plurality of discontinuous layers has a thickness of 100nm or less, the first portion and the second portion comprise the same material, and the second portion within 100nm of the functional coating from the discontinuous layer comprises an average microstructured crystal size that is less than the average microstructured crystal size of the first portion within 100nm from the discontinuous layer.

13. The coated article of claim 12, wherein the plurality of discontinuous layers comprises a refractive index difference of 0.1 or greater relative to any of the first and second portions, and wherein the thickness of each of the discontinuous layers is 5nm or greater.

14. The coated article of claim 12, wherein the coating comprises a surface roughness of 5nm Rq or less.

15. The coated article of claim 12, wherein the first and second portions comprise first and second bulk layers, respectively, each of the first and second bulk layers comprising a thickness of 200nm or greater.

16. The coated article of claim 15, wherein the first and second bulk layers are each in contact with at least one of the plurality of discontinuous layers.

17. The coated article of any one of claims 12-16, wherein the plurality of discontinuous layers comprises Al ₂ O ₃ 。

18. The coated article of any one of claims 12-16, wherein the substrate comprises a compressively stressed region extending from the major surface to a first selected depth in the substrate.

19. The coated article of any of claims 12-16, wherein the plurality of discontinuous layers comprise a thickness that is 10% or less of the total thickness of the functional coating.

20. The coated article of any one of claims 12-16, wherein the coated surface has a hardness of 12 or greater as measured by a berkovich nanoindentation at an indentation depth of 100nm or greater.

21. The coated article of any of claims 12-16, wherein the first portion and/or the second portion of functional coating comprises a polycrystalline or semi-crystalline material.

22. The coated article of any of claims 12-16, wherein the first portion and/or the second portion of the functional coating comprises a polycrystalline or semi-crystalline material comprising AlOxNy, wherein x (representing the mole fraction of oxygen relative to aluminum) is 0.02 to 0.25; and wherein y (representing the mole fraction of nitrogen relative to aluminum) is 0.75 to 0.98.

23. A method of forming a functional coating on a substrate comprising the steps of:

depositing a first portion on a major surface of a substrate;

depositing one or more discontinuous layers on the first portion, the one or more discontinuous layers comprising microstructures different from the microstructures of the first portion, the one or more discontinuous layers comprising an average optical transmission greater than 85% over the visible wavelength range of 450nm to 650 nm; and

depositing a second portion over the one or more discontinuous layers,

wherein the one or more discontinuous layers are configured to cause a change in the crystal growth behavior of the first portion and/or the second portion, the first portion and the second portion comprise the same material, and the second portion comprises an average microstructured crystal size within 100nm of the functional coating from the discontinuous layer that is less than the average microstructured crystal size of the first portion within 100nm of the discontinuous layer.

24. The method of claim 23, wherein the step of depositing one or more discontinuous layers further comprises the steps of:

the one or more discontinuous layers are deposited so as to have a thickness of 100nm or less.